Among my many notes from Naropa University from waaaay back when, i find this hand-scribbled, barely discernible lecture from one of my Tibetan Lama Teachers:
“If the mind is not contrived, it is spontaneously blissful, just as water, when not agitated, is by nature transparent and clear.”
My Teachers of Meditation would compare the mind in meditation to a jar of muddy water: The more we leave the water without interfering or stirring it? The more the particles of dirt sink to the bottom, letting the natural clarity of the water shine through. The very nature of the mind is such that if you only leave it in its unaltered and natural state, it will find its true nature, which is bliss and clarity.